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231.
Maged1, a new regulator of skeletal myogenic differentiation and muscle regeneration 总被引:1,自引:0,他引:1
Tuan HN Nguyen Mathieu JM Bertrand Christiane Sterpin Younes Achouri Olivier RY De Backer 《BMC cell biology》2010,11(1):57
Background
In normal adult skeletal muscle, cell turnover is very slow. However, after an acute lesion or in chronic pathological conditions, such as primary myopathies, muscle stem cells, called satellite cells, are induced to proliferate, then withdraw definitively from the cell cycle and fuse to reconstitute functional myofibers. 相似文献232.
233.
Evolution of SINE S1 retroposons in Cruciferae plant species 总被引:3,自引:0,他引:3
Lenoir A; Cournoyer B; Warwick S; Picard G; Deragon JM 《Molecular biology and evolution》1997,14(9):934-941
The S1 element is a plant short interspersed element (SINE) that was first
described and studied in Brassica napus. In this work, we investigated the
distribution and the molecular phylogeny of the S1 element within the
Cruciferae (= Brassicaceae). S1 elements were found to be widely
distributed within the Cruciferae, especially in species of the tribe
Brassiceae. The molecular phylogeny of S1 elements in eight Cruciferae
species (Brassica oleracea, Brassica rapa, Brassica napus, Brassica nigra,
Sinapis, arvensis, Sinapis pubescens, Coincya monensis, and Vella spinosa)
was inferred using 14-36 elements per species. Significant neighbor-joining
and maximum-parsimony phylogenetic clusters, supported by high bootstrap P
values and/or represented in 100% of the most-parsimonious trees, were
observed for each species. Most of these clusters probably correspond to
recent species-specific bursts of S1 amplification. Since these species
diverged recently, S1 amplification in Cruciferae plants is proposed to be
a highly dynamic process that could contribute to genome rearrangements and
eventually lead to reproductive isolation. S1 sequence analysis also
revealed putative gene conversion events that occurred between different S1
elements of a given species. These events suggest that gene conversion is a
minor but significant component of the molecular drive governing S1
concerted evolution.
相似文献
234.
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236.
C Boudry P Herlin B Plancoulaine E Masson A Elmoataz H Cardot M Coster D Bloyet J L Chermant 《Analytical cellular pathology》1999,18(4):203-210
The aim of the present study is to propose alternative automatic methods to time consuming interactive sorting of elements for DNA ploidy measurements. One archival brain tumour and two archival breast carcinoma were studied, corresponding to 7120 elements (3764 nuclei, 3356 debris and aggregates). Three automatic classification methods were tested to eliminate debris and aggregates from DNA ploidy measurements (mathematical morphology (MM), multiparametric analysis (MA) and neural network (NN)). Performances were evaluated by reference to interactive sorting. The results obtained for the three methods concerning the percentage of debris and aggregates automatically removed reach 63, 75 and 85% for MM, MA and NN methods, respectively, with false positive rates of 6, 21 and 25%. Information about DNA ploidy abnormalities were globally preserved after automatic elimination of debris and aggregates by MM and MA methods as opposed to NN method, showing that automatic classification methods can offer alternatives to tedious interactive elimination of debris and aggregates, for DNA ploidy measurements of archival tumours. 相似文献
237.
Jörg Barke Ryan F Seipke Sabine Grüschow Darren Heavens Nizar Drou Mervyn J Bibb Rebecca JM Goss Douglas W Yu Matthew I Hutchings 《BMC biology》2010,8(1):109
Background
Attine ants live in an intensely studied tripartite mutualism with the fungus Leucoagaricus gongylophorus, which provides food to the ants, and with antibiotic-producing actinomycete bacteria. One hypothesis suggests that bacteria from the genus Pseudonocardia are the sole, co-evolved mutualists of attine ants and are transmitted vertically by the queens. A recent study identified a Pseudonocardia-produced antifungal, named dentigerumycin, associated with the lower attine Apterostigma dentigerum consistent with the idea that co-evolved Pseudonocardia make novel antibiotics. An alternative possibility is that attine ants sample actinomycete bacteria from the soil, selecting and maintaining those species that make useful antibiotics. Consistent with this idea, a Streptomyces species associated with the higher attine Acromyrmex octospinosus was recently shown to produce the well-known antifungal candicidin. Candicidin production is widespread in environmental isolates of Streptomyces, so this could either be an environmental contaminant or evidence of recruitment of useful actinomycetes from the environment. It should be noted that the two possibilities for actinomycete acquisition are not necessarily mutually exclusive. 相似文献238.
239.
240.
Xavier Pepin Loïc Attali Catherine Domrault Sacha Gallet Jean M. Metreau Yannick Reault Philippe J. P. Cardot Mohamed Imalalen Catherine Dubernet Emilienne Soma Patrick Couvreur 《Journal of chromatography. B, Analytical technologies in the biomedical and life sciences》1997,702(1-2)
The major hypothesis underlying the remarkable efficiency of polyalkylcyanoacrylate particles loaded with doxorubicin against multidrug resistant tumor cells in vitro, is based on the ion-pair association of doxorubicin with soluble hydrolysis products of polyalkylcyanoacrylate. In an attempt to demonstrate the validity of this hypothesis, we have used ion-pair reversed-phase high-performance liquid chromatography and a laboratory-synthetized compound, i.e., the 2-cyano-2-butylhexanoic acid, as a model for polyalkylcyanoacrylate highly polydispersed degradation products. It is shown that, compared to a counter-ion, like heptane sulfonic acid, 2-cyano-2-butylhexanoic acid exhibits an effective ion-pairing effect at different pH values and organic mobile phase conditions. Moreover, at pH close to physiological conditions and at low mobile phase organic modifier percentage, this effect is experimentally observed, which strongly supports the initial hypothesis. 相似文献